Re: [PATCH 09/10] drm/i915/hdcp: migrate away from kdev_to_i915() in GSC messaging

[Jani Nikula <jani.nikula@intel.com>]

On Thu, 01 Aug 2024, Gustavo Sousa <gustavo.sousa@intel.com> wrote:
> Quoting Jani Nikula (2024-07-29 11:30:10-03:00)
>>Use to_intel_display() instead of kdev_to_i915() in the HDCP component
>>API hooks. Avoid further drive-by changes at this point, and just
>>convert the display pointer to i915, and leave the struct intel_display
>>conversion for later.
>>
>>The NULL error checking in the hooks make this a bit cumbersome. I'm not
>>actually sure they're really required, but don't go down that rabbit
>>hole just now.
>>
>>Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>>---
>> .../drm/i915/display/intel_hdcp_gsc_message.c | 67 +++++++++++++------
>> 1 file changed, 45 insertions(+), 22 deletions(-)
>>
>>diff --git a/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c b/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c
>>index 6548e71b4c49..35bdb532bbb3 100644
>>--- a/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c
>>+++ b/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c
>>@@ -7,6 +7,7 @@
>> #include <drm/intel/i915_hdcp_interface.h>
>> 
>> #include "i915_drv.h"
>>+#include "intel_display_types.h"
>> #include "intel_hdcp_gsc_message.h"
>> 
>> int
>>@@ -15,17 +16,19 @@ intel_hdcp_gsc_initiate_session(struct device *dev, struct hdcp_port_data *data,
>> {
>>         struct wired_cmd_initiate_hdcp2_session_in session_init_in = {};
>>         struct wired_cmd_initiate_hdcp2_session_out session_init_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !ake_data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>
> Hm... I'm afraid that wouldn't really work if drvdata was NULL, would
> it?
>
> With a NULL drvdata, I believe we would probably get a non-zero offset
> here.

Right, good catch. Not sure I want to add that check to everything in
to_intel_display() macro, because in most cases the passed in value
can't be NULL. Driver data is a bit different, though I don't think it
should really be NULL either.

BR,
Jani.



>
> --
> Gustavo Sousa
>
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         session_init_in.header.api_version = HDCP_API_VERSION;
>>         session_init_in.header.command_id = WIRED_INITIATE_HDCP2_SESSION;
>>@@ -72,17 +75,19 @@ intel_hdcp_gsc_verify_receiver_cert_prepare_km(struct device *dev,
>> {
>>         struct wired_cmd_verify_receiver_cert_in verify_rxcert_in = {};
>>         struct wired_cmd_verify_receiver_cert_out verify_rxcert_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !rx_cert || !km_stored || !ek_pub_km || !msg_sz)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         verify_rxcert_in.header.api_version = HDCP_API_VERSION;
>>         verify_rxcert_in.header.command_id = WIRED_VERIFY_RECEIVER_CERT;
>>@@ -135,17 +140,19 @@ intel_hdcp_gsc_verify_hprime(struct device *dev, struct hdcp_port_data *data,
>> {
>>         struct wired_cmd_ake_send_hprime_in send_hprime_in = {};
>>         struct wired_cmd_ake_send_hprime_out send_hprime_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !rx_hprime)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         send_hprime_in.header.api_version = HDCP_API_VERSION;
>>         send_hprime_in.header.command_id = WIRED_AKE_SEND_HPRIME;
>>@@ -183,17 +190,19 @@ intel_hdcp_gsc_store_pairing_info(struct device *dev, struct hdcp_port_data *dat
>> {
>>         struct wired_cmd_ake_send_pairing_info_in pairing_info_in = {};
>>         struct wired_cmd_ake_send_pairing_info_out pairing_info_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !pairing_info)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         pairing_info_in.header.api_version = HDCP_API_VERSION;
>>         pairing_info_in.header.command_id = WIRED_AKE_SEND_PAIRING_INFO;
>>@@ -234,17 +243,19 @@ intel_hdcp_gsc_initiate_locality_check(struct device *dev,
>> {
>>         struct wired_cmd_init_locality_check_in lc_init_in = {};
>>         struct wired_cmd_init_locality_check_out lc_init_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !lc_init_data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         lc_init_in.header.api_version = HDCP_API_VERSION;
>>         lc_init_in.header.command_id = WIRED_INIT_LOCALITY_CHECK;
>>@@ -280,17 +291,19 @@ intel_hdcp_gsc_verify_lprime(struct device *dev, struct hdcp_port_data *data,
>> {
>>         struct wired_cmd_validate_locality_in verify_lprime_in = {};
>>         struct wired_cmd_validate_locality_out verify_lprime_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !rx_lprime)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         verify_lprime_in.header.api_version = HDCP_API_VERSION;
>>         verify_lprime_in.header.command_id = WIRED_VALIDATE_LOCALITY;
>>@@ -330,17 +343,19 @@ int intel_hdcp_gsc_get_session_key(struct device *dev,
>> {
>>         struct wired_cmd_get_session_key_in get_skey_in = {};
>>         struct wired_cmd_get_session_key_out get_skey_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data || !ske_data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         get_skey_in.header.api_version = HDCP_API_VERSION;
>>         get_skey_in.header.command_id = WIRED_GET_SESSION_KEY;
>>@@ -382,17 +397,19 @@ intel_hdcp_gsc_repeater_check_flow_prepare_ack(struct device *dev,
>> {
>>         struct wired_cmd_verify_repeater_in verify_repeater_in = {};
>>         struct wired_cmd_verify_repeater_out verify_repeater_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !rep_topology || !rep_send_ack || !data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         verify_repeater_in.header.api_version = HDCP_API_VERSION;
>>         verify_repeater_in.header.command_id = WIRED_VERIFY_REPEATER;
>>@@ -442,6 +459,7 @@ int intel_hdcp_gsc_verify_mprime(struct device *dev,
>> {
>>         struct wired_cmd_repeater_auth_stream_req_in *verify_mprime_in;
>>         struct wired_cmd_repeater_auth_stream_req_out verify_mprime_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>>         size_t cmd_size;
>>@@ -449,11 +467,12 @@ int intel_hdcp_gsc_verify_mprime(struct device *dev,
>>         if (!dev || !stream_ready || !data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         cmd_size = struct_size(verify_mprime_in, streams, data->k);
>>         if (cmd_size == SIZE_MAX)
>>@@ -504,17 +523,19 @@ int intel_hdcp_gsc_enable_authentication(struct device *dev,
>> {
>>         struct wired_cmd_enable_auth_in enable_auth_in = {};
>>         struct wired_cmd_enable_auth_out enable_auth_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         enable_auth_in.header.api_version = HDCP_API_VERSION;
>>         enable_auth_in.header.command_id = WIRED_ENABLE_AUTH;
>>@@ -549,17 +570,19 @@ intel_hdcp_gsc_close_session(struct device *dev, struct hdcp_port_data *data)
>> {
>>         struct wired_cmd_close_session_in session_close_in = {};
>>         struct wired_cmd_close_session_out session_close_out = {};
>>+        struct intel_display *display;
>>         struct drm_i915_private *i915;
>>         ssize_t byte;
>> 
>>         if (!dev || !data)
>>                 return -EINVAL;
>> 
>>-        i915 = kdev_to_i915(dev);
>>-        if (!i915) {
>>+        display = to_intel_display(dev);
>>+        if (!display) {
>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>                 return -ENODEV;
>>         }
>>+        i915 = to_i915(display->drm);
>> 
>>         session_close_in.header.api_version = HDCP_API_VERSION;
>>         session_close_in.header.command_id = WIRED_CLOSE_SESSION;
>>-- 
>>2.39.2
>>

-- 
Jani Nikula, Intel